THE GENETIC RELATIONSHIP BETWEEN NAMA HISPIDUM AND NAMA- STEVENSII
By FATHI BASHIR ERTEEB ;/ Bachelor of Science Elfateh University 'I'ripoli, Libya 1976
Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE May, 1983 T ha..,~1s 19~ ~., . E "l'?::i~ u1~~\ '1..
.... : THE GENETIC RELATIONSHIP
BETWEEN NAMA HISPIDUM
AND NAMA STEVENSII
Thesis Approved:
li
1153186 i ACKNOWLEDGMENTS
I would like to express my sincere and deep appreciation to my major adviser Dr. Ronald J. Tyrl, for his invaluable advice, guidance, and encouragement throughout the course of this study. I gratefully thank Dr. Paul E. Richardson and Dr. Glenn Todd for serving as members of my committee and for their many helpful suggestions. Again I thank Dr. Paul E. Richardson and extend my thanks to Mr. Dave Ferris for their assistance in the use of the flourescent microscopy. Special thanks for my wife, Ftayem, my son Aymen and daughter Huda for their patience and sacrifice provided throughout the stay in the United States far from our family and not being able to see them for three and a half years. I wish also to thank Tina Ahern, Sandra Nobbe, and Donetta Bantle for the typing of this thesis.
iii TABLE OF CONTENTS
Chapter Page
I. INTRODUCTION 1
II. TAXONOMIC TREATMENT 6
III. STUDY SITES 13
IV. MORPHOLOGY • 23 V. GENETIC RELATIONSHIP • ...... 26 VI. CONCLUSIONS 44 BIBLIOGRAPHY 46
iv LIST OF TABLES
Table Page
I. Summary of Hitchcock's Treatment of Nama 10 II. Section Eunama Annual Species and the Position of Nama hispidum and Nama stevensii ...... 11 III. Nama hispidum and Nama stevensii Collection Sites ••••.•• '. . . . 15 IV. Summary of Fruit and Seed Set in Hybrid ization Experiments • • • . • • •• 27
V. Results of Exper-irnental Hybridization 28
v LIST OF FIGURES
Figure Page
1. Distribution of Nama hispidum and Nama stevensii in the United States and Mexico • . • • . • . . • . • . • • . 2
2. Collection Sites of Nama hispidum and Nama stevensii Used in Crossing Experiments • 14
vi CHAPTER I
INTRODUCTION
The genus Nama in the Hydrophyllaceae is composed of
18 annual species with 16 varieties and 20 perennial species and six varieties. Thus the genus includes 60 variable taxa. More than one-half of the species are distributed in the drier habitats of the southwestern United States and northern Mexico. There are five species in South America, two in the Caribbean, and one in Hawaii. Many of the taxa are restricted ·to a particular soil type while others do not exhibit this restriction for soil type.
In southwestern Oklahoma and adjacent Texas, Nama is represented by only two species (Hitchcock, 1933b; Water fall, 1969; Correll and Johnston, 1970). One is Nama stevensii collected by George W. Stevens in 1913 from near
Alva in Woods County, Oklahoma, and described by C. L.
Hitchcock when he monographed the genus in 1933. Nama stevensii is an obligate gypsophile found growing only on gypsum soils of western Oklahoma, Texas, and Mexico (Figure
1).
The second taxon is N. hispidum and was described
by Asa Gray in 1861. It is an extremely variable and wide
spread taxon found on sandy, gravelly soils. Plants are not
1 2
NAMA H\SP\OUM
NAMA STEVENS\\ figure 1. Distribution United of Naro•~ States ~Mexico. and~~ in the 3
found on gypsum soils. Populations of ~· hispidum occur from southwestern Oklahoma and Texas to southern California and northern Mexico (Figure 1).
Nama stevensii and ~· hispidum apparently are very closely related species. They differ, in addition to - soil type, in the nature of the pubescence, leaf shape and size, and the level of stamen filament insertion and the degree of filament fusion with the corolla. These charac ters are emphasized in the taxonomic keys used to different iate the two taxa (Hitchcock, 1933b; Waterfall, 1969;
Correll and Johnston, 1970). Nama stevensii is characterized by appressed hairs, linear-lanceolate leaves, and the adnate portion of the filament is much wider or dilated at the base than the free portion. In contrast N. hispidum has hispid hairs, linear-oblong to obovate leaves, and the adnate portion of the stamen filament is not much wider than the free portion. Further,~· stevensii has a rounded appearance because it bears branches at the base with the upper branches and leaves crowded; whereas,
~- hispidum appears to be more erect due to the lack of branching at the base and less crowding of the upper branches and leaves.
Even though these two taxa have been accepted as two species (Hitchcock, 1933b; Waterfall, 1979; Correll and
Johnston, 1970), there is still some questions as to whether the taxa are distinct. It was suggested by Correll and
Johnston that N. stevensii may be only a gypsophilous 4
phase of ~· hispidum. I. M. Johnston described a gypso philic variety of ~· hispidum from Nuevo Leon, Mexico in
1941 ~· hispidum var. gypsicola. Bacon (1974), how ever, believed that the affinities of this variety lay closer to ~- stevensii than to ~- hispidum, except for its prostrate habit, its shorter less dense pubescence, and its smaller leaves and in 1982 renamed the taxon as N. stevensii var. gypsicola.
Preliminary studies of N. stevensii and N. his- pidum by Tyrl Harmon County, Oklahoma, suggests the taxa may not be dis tinct entities. Nama, a most interesting genus, has received little detailed investigation since Hitchcock monographed the genus in 1933 and published additional work on Mexican species in 1939. During their investigations on the chromosome number of the Hydrophyllaceae, Constance and Cave (1947, 1950, 1959) and Constance (1963), reported chromosome numbers for about one-third of the species described by Hitchcock. Bacon (1974) reported chromosome numbers for about one-half of the species. Counts were also made by Tyrl et al. (1977). 5 The results of all three studies are smiliar. All plants exhibited a base chromosome number of seven with both N. hisoidum and ~- stevensii having 2~=14. Biosystematic study of N. stevensii and N. his- pidum was initiated by Tyrl in 1973. Grummer (1977) work ing with Tyrl studied the reproductive biology, analyzed the patterns of the morphological variation, characterized the flavonoid patterns by chromatography, and made intra- and interspecific crosses. However, the genetic information col lected by Grummer was imcomplete and the genetic relation ship of the two taxa was unresolved and needed to be clarified. Therefore, the objective of my study was to con duct an investigation of the genetic relationship of N. stevensii and ~· hispidum. Work involved a determina- tion of stigma receptivity, pollen fertility, selfcompati bility, and most importantly the genetic compatibility between the two taxa. CHAPTER II TAXONOMIC TREATMENT In his 1933 monograph of the genus, Hitchcock described the taxonomic and nomenclatural history of Nama. Majo.r points of his treatise are summarized below. In 1753, Linnaeus described the genus Nama and the species !i· zeylanicum. He described a second species,!· jamai cense in 1759. In 1763, he transferred~- zeylanicum to the genus Hydrolea and published the binomial H. zeylanica. Nama jamaicense was left in Nama. In the 1800's, additional species were described by Choisy, Gray, Hemsley, and others. In 1871, Watson described the genus Conanthus into which Heller in 1898 subsequently transferred numerous western U.S. species of Nama. Recognizing that the type species of Nama--N. zey- lanicum--had been transferred to another genus-- Hydrolea-- 1 Kuntze, in 1891 proposed that Nama be used only for !i· zeylanicum and other species of Hydrolea, and that all other species of Nama, including !i· jamaicense, be positioned in the new genus Marilaunidium. Because of the problem created by Linnaeus when he transferred the type species of Nama to Hydrolea and the taxonomic and nomenclatural ambiguity surrounding Nama, 6 7 the 1906 International Botanical Congress conserved the generic name Nama to include~· jamaicense as.the type. Conanthus and Marilaunidium thus became synonyms. Nama was revised in the 1800's by Choisy and Gray. The latter published many revisions of various taxa. In 1861 he examined the species of Nama known to him and on the basis of leaf position on the stem, leaf morphology, pubescence, and inflorescence type recognied eight species. He continued his work and in 1862 described two new species of Nama. In 1870, Gray revised his previous work, added new information, and using mainly the same characters, recog nized 15 species, four of which were new. In his treatment of the Hydrophyllaceae, Brand in 1913 again revised the genus. There were 2 subgenera, 2 sec tions, 36 species, 4 subspecies, 15 varieties, 6 forms and 1 hybrid recognied in this revision. He reduced the genus Conanthus to a subgenus of Nama with seven species characterized by united styles. He also reduced Marilauni dium to a subgenus with two sections comprising the remaind er of the species which are characterized by free styles. In distinguishing between the two sections, he used the level of stamen filament insertion from the corolla base. Species were differentiated from each other mainly by leaf length and serration, corolla length, stamen filament charac ters, and number of ovules. Brand in his treatment of the Hydrophyllaceae segre gated Andropus from Nama as a new genus. Unfortunately, 8 as Hitchcock Cl933a) points out Brand misinterpretated the stamen filament bases of Nama. Another new genus- Turricula--was proposed by Maedrib in 1917 to include N. parryi which he felt was markedly dissimilar to the other species of Nama. Finally, Hitchcock in 1933, questioning the status of the segregate genera and the status of some of the species of Nama, published the most recent and thorough monograph of the genus. Hitchcock, using length of the calyx lobes, style connation, growth habit, leaf margin and capsule characters, divided the genus into 5 sections. Three of these sections had one species each and one section had two species, one with two varieties. He reduced the subgenus Conanthus of Brand to a section composed of two species each with one variety characterized by fusion of styles. The semi-inferior ovary of !· stenocarpum was used to position it in a separate section. Nama rothrockii was placed in a different section because of its capitate inflor escence and crenate-dentate margined leaves. The cartila genous capsule with loculicidal and septicidal dehiscence of N. lobbii caused Hitchcock to classify it in a distinct section. The rest of the species are morphologically so homogeneous that he put them in a fifth section with 27 species and 18 varieties. The plants of this section CEunama} are divided into perennials and annuals and then species of each group are distinguished on the basis of inflorescence type, leaf morphology, pubescence, habit, 9 sepal characters, seed characters, and the length of the free portion of the filament in relation to the adnate portion (Table I). The Eunama section includes N. stevensii and N. hispidum with its 4 varieties. Table II lists the annual plants of this section and the position of ~· stevensii and N. hispidum. Hitchcock's monograph of this most interesting genus encouraged many botanists to make an effort to collect plants. Numerous specimens were collected from Mexico and southern Texas. Hitchcock examined these species and pub lished a second paper in 1939 describing three new species and one new variety. 10 TABLE I SUMMARY OF HITCHCOCK'S TREATMENT OF NAMA Section Species Section Distinguishing Characters Zonolacus N. stenocarpum Partially inferior ovary; styles frequently 3, united 2/3 their length, readily separable, capsule 120-250 seeded; annual. Conan thus li· densum Styles permanently connate at least 3/4 their length; fila- Ji.. aretioides ments unappendaged or minutely appendaged; capsule 10-35 seeded; annuals. Cinerascentia ,li. rothrockii Leaves crenate-dentate; inflorescence capitate; cap- sule 16-20 seeded; perennial. Arachnoidea £i.. lobbii Capsule cartilagenous and dehiscing loculicidally and septicidally; capsule 8-14 seeded; perennial. Eunama 17 annual species Capsule membranous and dehisc- ing loculicidally; capsule few 10 perennial -180 seeded; annuals and species perennials. 11 TABLE II SECTION EUNAMA ANNUAL SPECIES AND THE POSITION OF N. HISPIDUM AND N. STEVENS!! Species Taxonomic and/or Ecological Notes N. sandwicense Endemic to Hawaii. N. torynophyllum Mexico; 50-90 seeds/ capsule. N. pusillum Leaves rhombic-ovate to obovate, 6-13 mm long; 20-40 seeds/ capsule. N. depressum Leaves linear spathulate to narrowly oblong-spathulate, 10-30 mm long; 16-30 seeds/ capsule. N. schaffneri Leaves oblong, oblong-lanceolate or spathulate, 2-6 cm long; filament scales widened and toothed above. N. undulatum Filament scales narrow, not toothed. N. biflorum Long-lived annual or biennial. N. jamaicense Leaves spathulate, 6-15 mm long. N. stevensii Obligate gypsophile; leaves linear- lanceolate, 5-8 mm long. N. demissum Leaves obovate to spathulate or linear-lanceolate, 5-8 nun long. N. ehrenbergii Leaves obovate, 15 mm long, styles connate to middle. N. havardii Long-lived annual or biennial; leaves oblong, elliptic to obovate, 2-4 cm long. 12 TABLE II (Continued) Species Taxonomic and/or Ecological Notes N. dichotomum Leaves linear elliptic, 5-30 mm long. N. parvifolium Leaves spathulate to obovate-oblong, 7-15 mm long; 60-80 seeds/ capsule. N. prostratum Leaves ovate rotund, 8-20 mm long and 6-12 mm wide. N. coulteri Leaves obovate or spathulate, 1-3 cm long. N. hispidum Leaves linear-oblong to obovate, 1-5 cm long. CHAPTER III STUDY SITES Nama hispidum and ~· stevensii were collected at twenty-two study sites in western and southwestern Oklahoma and Texas (Table III, Figure 2). The two taxa were growing together in only one population, located in Harmon County, Oklahoma. Selected plants were dug up, transplanted into pots, and subsequently transported to the University of Oklahoma Biological Station on Lake Texoma and/or to the Botany Department greenhouse at Oklahoma State University for further study and manipulation. 13 14 ••• Figure 2. Collection Sites of Nama hispidum and Nama stevensii Used in Crossing Experiments. Squares,!· hispidum; Circles,!· stevensii; Star, Mixed Population. TABLE III NAMA HISPIDUM AND N. STEVENS!! COLLECTION SITES Population County Range Township Section Notes Number 542 Blaine Rl2W Tl9N 27 N. stevensii. 8.3 miles w. of intersection of OK Hwy 58 with OK 759 Hwy 51; 300 yds. N. of Hwy on sec- tion line road. Top of gyp ridge. Okeene, OK. 543 Custer Rl5W Tl3N 36 N. stevensii. Gyp outcrop S. 762 side of paved section road. 1.3 mi. W. of OK Hwy 54 and 3 mi. N. of U.S. Hwy 66 junction, Weatherford, OK. I-' l11 ...... °' . ca 2 w. of of W. Lake S. mi. House, W. S. of about N. 1.8 OK. butte due Cut, Court waterway Crowder outcrop mi. outcrop OK. 1 road. Co. 34. Gyp Gyp Sandy Notes cemetery, and junction, sandstone area. Corn, Hwy 54 Greer 66 of of section OK OK. of Hwy NE Hwy launch of of base s. stevensii. stevensii. hispidum. OK mi. 5 boat the. U.S. side N. N. side Weatherford, N. of mi. Magnum, 29 5 11 (Continued) Section III Tl2N TllN T4N TABLE Township Rl5W Rl4W Range R22W Washita Custer County Greer 761 544 546 545 Number Population TABLE III (Continued) Population County Range Township Section Notes Number 547 Harmon R24W TSN 21 N. stevensii. Gyp outcrop s. side of OK Hwy 9. Ca. 0.8 mi. w. of Greer Co. line, OK. 548 Harmon R26W TlN 5 N. hispidum and~· stevensii. 549 Gyp bluffs abutting the Red River flood plain. 0. 25 mi. NE of bridge over river on Hollis-Goodlet Road along ditch bank and fence row adjacent to field. OK. 550 Jackson R26W Tl5N 6 ~· hispidum. 0.5 mi. N. of OK 773 Hwy 34-44 bridge across Red River. Stabilized sand dune E. side of Hwy next to abandoned RR building. OK. ...... -.....) TABLE III (Continued) Population County Range Township Section Notes Number 551 Wilbarger R20W T2S 6 !:!_. hispidum. 0.3 mi. S. of 774 (Texas) Red River bridge on U.S. Hwy 283. Stabilized sand dunes of river deep sand soil. Very common. Texas. 552 Caddo RlOW T6N 35 N. stevensii. Western of 775 Cement oil field adjacent to OK Hwy 8, Ca. 5.0 mi. W. of Cement OK Post Office. Exposed gyp ridge, scat- tered plants. OK. 553 Caddo RlOW T9N 18 !:!_. hispidum. 3.8 mi. W. of OK 776 Hwy 152 and 8 junction. Open area SW facing slope at base of bluffs next to private driveway, Ca. 300 I-' 00 TABLE III (Continued) Population County Range Township Section Notes Number meters E. of Salary Lake. OK. 760 Major Rl3W T22N 6 N. stevensii. 5.2 mi. W. of Orienta. N. side of the OK Hwy 15. On top of a gyp butte. OK. 554 Motley N. hispidum. About 2.0 mi. N 767 (Texas) of Matador. w. side of Texas Hwy 70. Stabilized sand. Numerous small, weak plants due to the drought. Texas. 555 Lubbock ~- hispidum. Lubbock. On N. 770 c•rexas) side of the 4th St. w. of the Albertson food and drug store. Disturbed sand dune, area of the I-' \0 TABLE III (Continued) Population County Range Township Section Notes Number city development. Huge prostrate plants. Few. Texas. 556 Lubbock ~· hispidum. N of Lubbock city 769 (Texas) limits, s. of Regis St. Exit 847 W. of TX Hwy 27. Scattered plants. Texas 557 Lubbock ~· hispidum. E. of Lubbock. 768 (Texas) 4th St. (=TX Hwy 82) and Quirt Ave. s. side of the 4th St. Sandy clayey soil. Common. Texas 558 Cottle ~· hispidum. Ca. 0.2 mi. E. of 765 (Texas) Paducah city limits s. side of TX Hwy 70. Few plants. Endangered tv 0 TABLE III (Continued) Population County Range Township Section Notes Number plants. Texas. 763 Beckham R25W T8N 7 N. stevensii. 9.2 mi. S. of OK Hwy 30 from I-40. Roadside gyp outcrop. 764 Cottle N. stevensii. .47 mi. N. of (Texas) river bridge, ca. 18.8 mi. N. of Paducah, Gyp bluffs W. side of TX Hwy 83-62. Plants are common. 766 Motley N. stevensii. Gyp S. side of (Texas) TX Hwy 70-62 on ridges of waterway. Ca. 13.9 mi. E. of Matador, TX. 771 Foard N. stevensii. Gyp S. side of (Texas) IV I-' TABLE III (Continued) Population County Range Township Section Notes Number TX Hwy 70. 5.3 mi. W. of Crowell. Plenty of plants. Texas. 772 Hardman ~- hispidum. 5.1 mi. s. of (Texas) bridge. Sandy s. side of Goodlet- Hollis Road. Scattered plants. N N CHAPTER IV MORPHOLOGY The plants of Nama vary from herbaceous to suffrutes cent, prostrate to erect, rarely glabrous to variously pubes cent, and are 2 - 80 cm tall. The leaves are quite variable in shape and size. They range from linear to lanceolate, ovate, spathulate, obovate, oblanceolate,oblong, or a combination of each two of these shapes. They are 0.5 - 8 cm long and 0.1 - 3 cm wide, mostly alternate and entire. The flowers are born singly in the leaf axils or in reduced, lateral or terminal clusters of 2, 3, or 5. Pedicels are present or absent. The calyces are typically divided to the base with linear-lanceolate to spathulate lobes. The corolla is tubular to obconic-campanulate and glabrous. There are five stamens, typically unequal in length and subequal to unequally inserted. The filament bases are usually somewhat dilated and the adnate portion may or may not have free margins which are usually glabrous. The styles are typically two, usually free, but sometimes partially or almost completely united. The single ovary is one locular but seemingly two-chambered by the intrusions of the pla centa. The ovary is typically pubescent. The fruit is ovoid to globose, many seeded capsule which is loculicidal ly, or rarely septicidally, dehiscent. It is membranous or 23 24 cartilagenous. The seeds are yellow or brown, variously pit ted, alveolate, reticulate, or smooth. They are sometimes minutely, transversely corrugated as well as pitted. The pollen grains are fairly uniform and differ primarily in the diameter of the lumina between the central zone of the meso colpia and the area adjoining poles and colpia (Constance and Chung, 1982). Taxonomic keys distinguishing ~· stevensii and N. hispidum generally emphasize the leaf shape and pubes- cence and stamen features. For example, characters of N. stevensii are: leaves linear-lanceolate, calyx pubescence closely appressed and stamen filament bases dilated. In con trast, the characters of ~· hispidum generally are: leaves linear-oblong to obovate, calyx pubescence somewhat spreading, and filament bases not dilated. N. stevensii as observed by me and as described by Hitchcock Cl933b) and Correll and Johnston (1970) is grayish strigose, erect or ascending, few branched, 4-8(25) cm tall. The plants branch at the stem base and form dense rounded clumps. The leaves are linear-lanceolate, acuminate, 1-3 cm long and 1.3 mm wide, strongly revolute, sessile and some what clasping. The flowers are borne in leafy terminal or axillary clusters of 2's or 3's. The leaves usually exceed the flowers which are lavender. The sepals are linear lanceolate and 5-8 mm long. The corolla is tubular to fun nelform and 8-10 mm long. The stamens are about half the corolla length. The stamen filaments are terete 1-2 mm long 25 and the filament bases are dilated with narrow marginal wings. The base usually equals the free filament portion in length. The styles are two about 4 mm long. The capsules have 40-50 seeds which are yellow, 0.3 rrun long and alveo late. !· hispidum is strigose-hirsute to hispid, erect or ascending and 8-35 (40> cm tall. The plants branch sparingly from the base or only above. The leaves are vari able, linear to linear-oblong, spathulate to obovate, 1-3 (5) cm long and 1-7 rrun broad; they are slightly to strongly revolute, mostly narrow toward the base. The flowers are solitary or borne in 2-3 flowered terminal cymes and are pink to bright purple. The sepals are linear lanceolate, 4.0-7.0 rrun long. The corolla is tubular-campan- ulate, 8-15 rrun long. The stamens do not exceed half the length of the corolla. The filaments are rather thick terete and very unequally inserted, 1-4 rrun from the corolla base. The fila ment bases are scarcely dilated, i.e., the adnate portion is not much wider than the free filament. The margins are not winged. The two styles are 2-4 rrun long. The capsules have 20-100 seeds. The seeds are 0.5 mm long, yellow and minute ly alveolate-reticulate (Hitchcock, 1933b; Correll and Johnston, 1970). CHAPTER V GENETIC RELATIONSHIPS With the exception of one mixed population in Harmon County,~· hispidum and N. stevensii grow in sepa- rate populations in Oklahoma and adjacent Texas. Morpholog, as noted above, is of limited value in determining relation ships. The two taxa have the same chromosome number C2n=l4). When taxa are allopatric, have intergrading morphology, and have the same chromosome number, as in Nama, a genetic approach to taxonomy involving artificial hybridization is needed (Thompson, 1960). The genetic approach measures the genetic relationship directly between taxa and the analysis of data from experimental hybridiza tion gives a better understanding of this relationship. Elucidation of gene flow patterns within each taxon and between the two taxa were examined utilizing standard hybrid ization techniques (Radford et al., 1974). Crosses were performed on established potted plants at the University of Oklahoma Biological station and at the Botany Department greenhouse at Oklahoma State University in the summers of 1981 and 1982 respectively. The results of these hybridiza tions are summarized in Table IV and v. The results of phenological studies made at the time 26 27 TABLE IV SUMMARY OF FRUIT AND SEED SET IN HYBRIDIZATION EXPERIMENTS . Cross Number of Numoer of Nu~er of < crosses fruits deveiooed fruit set seeds/ovules seed se: Se1 f Cor.mati o i1 i ty N.. ~isoidur"'l 33 G 0 0 0 ,, stevensii 0 0 '.) J ''· ~-"' Intraoooulational N. hisoidum x !!· hisoidum i3 13 100 495/597 83 ~, ·c:~ N. stevensii x :,... stevensii 100 ..,..;1 ...... 100 :nteroopu1ationa1 ~1. hisoicu:n x N. hisoidum .I-- 28 '9 582/946 53.3 "·" stevensii x N. s:evensii 61 39 64 1522/1686 !!0 Intersoecific !:!.· hisoidum x !!· stevensii 149 lOi n .a 503/4284 11 s 7 N. stevensii x N. hiscidum 164 109 66.5 66/2873 2.3 28 TABLE V RESULTS OF EXPERIMENTAL HYBRIDIZATION Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced Inters12ecif ic SSOb X 543c 1 1 0/43 SSOb X 547d 1 0 0/0 550b x 552e 1 1 0/25 550c X 542e 1 1 0/46 550c x 544e 1 0 0/0 550c x 549a 1 1 0/57 550d x 546e 1 0 0/0 SSOd X 547b 1 0 0/0 55lb x 544e 1 0 0/0 55lb x 546a 1 0 0/0 55lb x 546c 1 0 0/0 55lc X 552a 1 1 0/25 55ld X 547d 1 0 0/0 553b x 542c 1 1 0/45 553b x 544a 1 1 0/26 553b x 547b 1 1 5/34 553b x 552e 1 0 0/0 553c X 542a 1 1 12/18 553c x 549c 1 1 0/14 765d x 759c 3 0 0/0 765d x 766e 1 0 0/0 767e x 759a 1 1 0/57 29 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 767e x 762c 2 0 0/0 770d x 762c 1 1 0/0 772c x 761c 2 2 1/61 772c X 76le 1 1 0/10 773a X 759a 4 2 25/103 773a X 76lb 2 1 2/40 773a X 761c 2 2 0/76 773a X 76ld 2 2 2/64 773a x 76le 1 1 0/45 773a X 762a 2 2 9/114 773a x 762c 2 1 1/46 773a X 762b 1 0 0/0 773a x 762d 1 0 0/0 773a x 762e 1 1 * 773a x 763c 1 0 0/0 773a X 763e 1 0 0/0 773a X 766e 2 2 15/61 773b x 759a 2 0 0/0 773b x 760b 3 2 1/72 773b x 761c 1 1 0/30 773b x 762d 3 1 0/53 773b x 763d 1 1 0/15 773b x 759a 1 1 8/38 773c X 759b 2 2 0/90 30 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 773c X 759c 1 1 15/21 773c X 759e 2 2 23/67 773c X 760a 2 2 5/35 773c x 76lc 1 1 0/21 773c X 76ld 3 3 0/123 773c X 76le 2 2 0/88 773c x 762d 8 8 17/335 773c X 762e 1 1 0/20 773c x 763c 2 1 0/41 773c x 766c 1 1 1/36 773c x 775c 2 2 0/83 773c X 775e 3 3 2/121 773d x 763c 4 3 2/146 773e x 759a 1 1 0/52 773e X 759c 1 1 4/25 773e X 760b 3 3 0/136 773e x 762c 2 2 6/72 773e X 762d 3 3 7/147 773e X 775a 2 2 4/131 774b x 77lb 1 0 0/0 774c X 760a 1 1 26/65 774c X 762d 7 7 64/ 416 774c X 763c 2 2 0/72 774d x 759a 1 0 0/0 31 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 774d x 760b 3 1 4/20 774d x 76ld 1 1 8/46 774d x 762c 1 1 12/40 774d x 762d 5 4 47/147 774d x 763c 2 1 10/60 774d x 763d 4 4 67/202 774e x 760a 1 1 0/23 776a X 763c 1 0 0/0 776a x 766a 1 1 65/65 776b x 759a 4 0 0/0 776b x 760b 1 1 0/10 776b x 76ld 2 1 3/60 776b x 762c 1 1 * 776b x 763a 1 0 0/0 776d x 762c 1 1 30/50 542a x 557a 1 0 0/0 542b x 553d 1 0 0/0 542c x 553b 1 0 0/0 542c X 557d l 0 0/0 542d x 550d 1 0 0/0 542e x 550c 1 0 0/0 543b x 550d 1 1 0/45 543c X 557a 1 1 0/0 543c X 557d l 1 0/55 32 TABLE V {Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 543d x SS Ob 1 1 1/41 543d x SSOd 1 0 0/0 543d x 553c 1 0 0/0 543d x 553d 1 1 0/55 543e X 557a 1 0 0/0 544a x 545b 1 0 0/0 544a x 553b 1 0 0/0 544b x 550d 1 1 0/13 544d x 557e 1 0 0/0 546a x 55lb 1 0 0/0 546a x 558b 1 0 0/0 546b x 556e 1 0 0/0 546c X 556a 1 1 1/38 546c X 557a 1 1 0/39 546c X 558b 1 1 0/36 546d x 550c 1 0 0/0 546e X 550c 1 0 0/0 546e x 550d 1 1 0/33 547a x 558b 1 1 0/36 547b x 553b 1 0 0/0 547c X 558b 1 0 0/0 547d x 55ld 1 0 0/0 547e X 556e 1 0 0/0 549a X 550c 1 0 0/0 33 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 549c X 553c 1 0 0/0 549c X 557a 1 0 0/0 552a x SS le 1 0 0/0 552a x 558b 1 0 0/0 552e X SS Ob 1 0 0/0 552e X SS le 1 0 0/0 759a x 773c 1 0 0/0 759c X 765d 2 2 3/28 759c X 773c 1 1 1/26 759d x 776e 1 0 0/0 759e x 769b 4 4 0/203 759e X 773a 1 1 0/20 759e X 773c 4 4 0/171 760a X 765b 2 0 0/0 760a X 776e 1 0 0/0 76lb x 765d 1 0 0/0 76lc X 765d 1 0 0/0 76lc X 767f 1 1 0/20 76lc X 773a 1 1 * 76lc X 773c 1 1 0/49 76lc X 774c 1 0 0/0 76ld x 765d 1 0 0/0 76ld x 773a 1 1 1/21 76ld x 773c 6 5 1/169 34 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 76ld x 773e 2 2 1/56 76ld x 774d 3 3 3/90 76ld x 776b 8 4 1/123 76le X 773e 1 1 0/43 762a x 773c 4 3 0/96 762b x 773a 5 5 13/151 762b x 773c 5 5 8/148 762b x 773e 1 0 0/0 762b x 774d 1 1 0/60 762c x 773a 1 1 2/22 762c x 773c 1 1 0/11 762d x 765a 1 0 0/0 762d x 767e 3 3 0/130 762d x 773b 3 1 0/18 762d x 773d 2 1 0/45 762dX 773e 2 1 0/25 762d x 774c 5 1 0/25 762d x 774e 2 1 0/20 762d x 776b 3 1 0/10 762d x 776d 1 1 10/60 762d x 776e 2 1 0/20 762e X 774c 4 4 0/155 763b x 776b 2 0 0/0 763c X 773c 2 2 2/89 35 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 763c x 774d 2 2 0/94 763c x 776b 3 3 1/125 763d x 773a 2 2 1/35 763e x 773c 3 1 0/14 766e x 765d 2 1 16/35 766e x 773a 2 1 0/13 766e x 773e 1 0 0/0 766e x 774c 2 0 0/0 775a x 768e 1 0 0/0 775a x 765d 1 1 0/32 775a x 773a 1 1 0/0 775a x 773c 1 0 0/0 775a x 773e 1 1 0/0 775e x 773c 2 1 0/30 775e x 773e 1 0 0/0 InterEOEulational 545b x 550b 1 0 0/0 550a x 558a 1 0 0/0 550b x 55lc 1 1 12/63 550c X 556e 1 1 25/29 550d x 55lc 1 0 0/0 SS lb x 558a 2 0 0/0 SS lb x 557a 1 0 0/0 36 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 55lc X 550d 1 1 47/50 553c X 556a 1 0 0/0 553c x 557a 1 0 0/0 553c x 558a 1 0 0/0 553e X 550c 1 0 0/0 553e X 55lc 1 0 0/0 557d x 556b 1 1 27/39 767f x 776c 1 1 29/31 770c X 773b 2 0 0/0 770d x 773d 1 1 0/25 772b x 768e 1 0 0/0 772c X 770c 2 1 22/23 772c x 774c 1 0 0/0 772c X 774e 1 0 0/0 772e X 770c 1 0 0/0 772e X 773c 1 1 * 772e X 776a 1 1 * 773a X 776a 1 1 44/47 773c X 765a 1 1 2/58 773c X 770a 2 2 26/99 773c X 770e 2 2 30/56 773c X 774c 4 4 170/170 773e X 770c 1 1 0/20 773e X 77ld 1 1 79/79 37 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed ovules Produced 773e X 775a 1 1 14/34 774b x 773e 1 1 20/27 774c X 770c 1 0 0/0 774c X 773c 1 0 0/0 774d x 768b 1 1 0/20 774d x 770b 1 1 35/35 774e X 767e 1 1 * 774e X 772c 1 0 0/0 776a X 768b 3 0 0/0 776a x 772e 2 1 0/14 776b x 773a 2 1 0/27 776b x 772e 3 0 0/0 542b x 543e 1 0 0/0 542b x 549c 1 0 0/0 543a X 546b 1 1 97/102 543a X 546e 1 0 0/0 543a X 547b 1 1 28/35 543c X 549c 1 1 89/89 543d x 542b 2 2 71/76 544b x 542c 1 1 8/15 544c X 543e 1 0 0/0 544c X 546c 1 1 31/34 544c X 546d 1 0 0/0 38 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 544d x 546a 1 0 0/0 544d x 546d 1 0 0/0 546a x 549a 1 1 14/17 546b x 543a 1 0 0/0 546b x 544d 1 0 0/0 546c X 543e 1 0 0/0 546e X 542b 1 1 14/17 546e x 544a 1 0 0/0 546e X 549a 1 0 0/0 /~ 547c x 546d 1 0 0/0 / 549a x 544d 1 0 0/0 549d x 542a 1 1 45/48 552a X 542a 1 1 27/29 552a X 549c 1 1 24/26 552d x 546b 1 0 0/0 759a x 763c 2 1 60/60 759a x 760e 1 1 33/33 760c x 763a 1 1 53/53 76lb x 763e 1 0 0/0 76lc x 760a 1 1 80/81 76lc X 763c 1 1 41/44 76lc X 763e 2 2 86/88 76lc X 77ld 4 4 262/269 39 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 76ld x 763e 2 1 23/26 762a x 775c 1 1 15/15 762c X 76lc 1 1 9/15 762d x 759a 3 3 150/173 762d x 775a 1 1 53/53 766e X 762d 9 5 140/153 775a X 762d 1 0 0/0 775c X 762d 3 3 70/94 IntraEoEulational 55lc X 55lb 1 1 21/26 767e X 767f 1 1 0/30 773a X 773b 1 1 53/56 773a X 773c 1 1 73/86 773b x 773a 2 2 45/56 773c X 773a 2 2 94/108 773c X 773b 1 1 34/34 773c X 773e 2 2 125/130 773e X 773c 1 1 50/58 776d x 776e 1 1 0/13 762d x 762f 1 1 53/53 Self ComEatibility 550b x 550b 1 0 0/0 550d x 550d 2 0 0/0 40 TABLE V {Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed ovules Produced SS la x SS la 1 0 0/0 SS le x SS le 1 0 0/0 553c x 553c 1 0 0/0 767f x 767f 1 0 0/0 770d x 770d 2 0 0/0 770e x 770e 2 0 0/0 772c x 772c 4 0 0/0 772e x 772e 2 0 0/0 773a x 773a 5 0 0/0 773c x 773c 6 0 0/0 773d x 773d 2 0 0/0 774c X 774c 4 0 0/0 542d x 542d 1 0 0/0 543c x 543c 1 0 0/0 544c X 544c. 1 0 0/0 544d x 544d 1 0 0/0 546a X 546a 1 0 0/0 546d x 546d 1 0 0/0 546e x 546e 1 0 0/0 549c x 549c 1 0 0/0 759e x 759e 1 0 0/0 76lc X 76lc 1 0 0/0 762d x 762d 7 0 0/0 41 TABLE V (Continued) Cross Number Number of Seed Set/ of Crosses Fruits Developed Ovules Produced 762e X 762e 2 0 0/0 763c X 763c 1 0 0/0 766e X 766e 1 0 0/0 * = Sample lost 42 that the crosses were performed, including flowering sequences and stigma receptivity, agree with those obtained by Grumer (1977). In these studies it was noted that the self-pollination does not occur naturally due to a slight spatial separation of the stigmas and anthers and the manner of anther dehiscence which is extrose. The presence of the insect pollinators Sphecodosoma and Nomadopsis is crucial in nature (Grummer, 1977). Pollen fertility was determined by making slide counts of pollen grains stained with aniline blue-lactophenol. Fertility was 86 to 95%. The results of the manual self-pollination of 57 flowers of both taxa revealed that both are genetically self-incompatible with no fruit development nor seed set. These results were supported by sequential sectioning of the style (technique of Ramming et al., 1973) which indicated a failure of continuing pollen tube growth. Even though there is germination of pollen grains on the stigmas and growth through the upper parts of the style, growth ceases before the ovules are reached. In contrast, the remnants of pollen tubes can be seen easily in the ovary and in the ovules of cross-pollinated flowers. The crosses among the plants of an individual popula tion were highly successful. Both fruit and seed set was high. The same was true for crosses among plants of dif ferent populations. Both taxa were similar. Most important is the determinatin of gene flow between 43 the two taxa. Two hundred-sixteen capsules developed in three hundred-fourteen reciprocal crosses. All capsules appeared normal in size; however, upon dissection, it was discovered that seed set was greatly reduced. Seeds ranged from very small, black, grayish-green and shriveled to full size and yellow. Seed development was determined to be 8.0%. This percent is much lower than that recorded by Grummer (1977) which was 26.73%. This reduction may be due to use of Texas populations of the variable ~· hispidum rather than Oklahoma populations in the hybridizations. I was not able to germinate the seeds obtained from the crosses. CHAPTER VI CONCLUSIONS Nama stevensii and ~· hispidum are more similar to each other than to any other taxon in the genus. This similarity and the overlap in the characters usually used to distinguish the two taxa raised the question as whether they are distinct species or merely two genetic phases--ecotypes, varieties or subspecies of one species. The two taxa have similar phenological and genetic patterns. However, they differ consistently in only two distinguishable characters, namely the soil type on which they grow and the nature of their pubescence. They are highly restricted as to the soil type upon which they grew. The data obtained in the experimental hybridizations give information about their genetic relationship. Gene flow between the two taxa is greatly reduced. Although cap sules develop, seed set is highly reduced. rt.appears that there is an almost complete block to the exchange of genetic information between the two taxa. However, the development of the capsules and the formation of some seeds is signif i cant, indicating there is a slight possibility of gene flow. These genetic data when combined with those from morph ology and phenology suggest that the taxonomic recognition 44 45 of these two taxa as species best reflects their biological relationship. They are morphologically, ecologically, and genetically distinct. On the basis of the information collected to date, one might hypothesize that the widely distributed and variable Nama hispidum has given rise to the gypsophilic Nama stevensii. This hypothesis is supported by the reclassi fication of Nama hispidum var. gypsicola (Johnston, 1941) to Nama stevensii var. gypsicola (Bacon, 1982). Examination and comparison of the plants of this variety convinced me to agree with Bacon that this taxon is N. stevensii rather than ~· hispidum. The description of numerous gypsophiles in the genus Nama suggests that such an evolutionary phenomenon is possible. The marked similar ities in morphology, insect visitors as described by Grummer (1977), flowering and the incomplete barrier to gene ex change are indicative of a relative recent origin. BIBLIOGRAPHY Bacon, J. D. "Chromosome numbers and taxonomic notes in the genus Nama CHydrophyllaceae)." Brittonia 26 (1974)-;-TOl-105. New species of Nama CHydrophyllaceae) from the Chihuahuan desert region of Mexico. Sida 9(2) (1982), 99-103. Benenati, M. "The relationship between Nama stevensii and!!· hispidum." M.S. Thesis, University of Okla homa, Norman, Oklahoma, (1974). Brand, A. "Hydrophyllaceae." In Engler, Das Pflanzen reich, IV, Fam. 251 (1913), 1-186. Cave, M. s. ·and Constance, L. "Chromosome number in the Hydrophyllaceae." III. Univ. Calif. publ. Bot. 18 ( 194 7) , 449-465. "Chromosome number in the Hydrophyllaceae." IV. Univ. Calif. Publ. Bot. 23 (1950), 363-3~ -- -- "Chromosome number in the Hydrophyllaceae." V. Univ. Calif. Publ. Bot. 30 Cl959), 233-258. Constance, L. "Chromosome number and classification in Hydrophyllaceae." Brittonia 15 (1963), 273-285. Constance, L. and Chung, T. I. "Sem survey of pollen morphology and classification in Hydrophyllaceae." Amer. Jour. Bot. 69 (1982), 40-53. Correll, D. S. and Johnston, M. C. Manual of Vascular Plants of Texas. Texas Research Foundation. Renner,'fexas. 1970. Gray, A. "Characters of new or obscure species of plants of Monopetalous orders in collection of the United States South Pacific exploring expedition." Deadalus Amer. of Arts and Science 5 (1861), 321-352. 46 47 "Characters of new or obscure species of plants of Monopetalous orders in collection of the United States South Pacific exploring expedition." Deadalus Amer. Acad. of Arts and Science 6 (1862), ~ Grurruner, B. D. "A biosystematic study of the relationship of Nama hispidum and !:!. • stevensii." M. s. Thesis. Oklahoma State University, Stillwater, Oklahoma, (1977). Hitchcock, C. L. "A taxonomic study of the genus Nama I." Amer. Jour. of Bot. 20 (1933a), 415-431. "A taxonomic study of the genus Nama II." Amer. Jour. of Bot. 20 (1933b), 518-534. ~~ "The perennial Mexican Nama." Amer. Jour. of Bot. 26 ( 1939 > , 341-34 7-.- Johnston, I. M. "Gypsophily among Mexican desert plants." J. Arnold Arbor. 22 (1941), 145-170. Linnaeus, C. Species Plantarum. Vol. 1 ed. 1. Ray Society, London, Cl 753). Radford, A. E., Dickison, w. c., Massey, J. R., and Bell, c. R. Vascular plants systematics. Harper and Row, New York (1974). Ramming, D. W., Herman, H. A., and Richardson, P. E. "Sequential staining of callose by aniline blue and lacmoid for flourescence and regular microscopy on a durable preparation of the same specimen." Journal article No. 2547 (1973), Oklahoma State University, Agricultural Experiment Station, Stillwater, Oklahoma. Thompson, H. J. "A genetic approach to the taxonomy of Mentzelia Lindleyi and .t!· crocea (Loasaceae)." Brittonia 12 (1960), 81-93. Tyrl, R. J., Bruner, J. L., and Phillippi, M. A. "Chromosome numbers in Nama and Proboscidea," IOPB Chromosome Reports. TaXO'ri""""26 (1977), 559. Waterfall, U. T. Keys to the Flora of Oklahoma. The Student Union Bookstore, Oklahoma State University, Stillwater, Oklahoma 1969. I VITA Fathi Bashir Erteeb Candidate for the Degree of Master of Science Thesis: THE GENETIC RELATIONSHIP BETWEEN NAMA HISPIDUM AND NAMA STEVENSII Major Field: Botany Biographical: Personal Data: Born in Tripoli, Libya, March 20, 1952; the son of Bashir A. Erteeb and Kheiria A. Deyab. Education: Graduated from Ali Nij jar High School, Tripoli, Libya in June 1972; received the Bachelor of Science degree in Botany and Chemistry from Elfateh University in June 1976; completed requirements for the Master of Science Degree at Oklahoma State University in May, 1983. Professional Experience: Worked with the Department of Botany at Elfateh University, Tripoli, Libya, as a graduate teaching and research assistant from October 1976 to December 1979; during this period joined the "Flora of Libya Project" which was being done by the taxonomists of the Department and financed by the Arabic Development Institute, Tripoli, Libya; gave a seminar at the annual meeting of Oklahoma Academy of Science, November 1982, as part of professional training.